This invention is a continuation-in-part of U.S. patent application Ser. No. 08/629,057, entitled LINEAR ABLATION ASSEMBLY, filed Apr. 8, 1996, the disclosure of which is incorporated by reference herein.
This invention generally relates to the detection and elimination of cardiac arrhythmia and particularly atrial fibrillation.
Atrial fibrillation is the disorganized depolarization of a patient's atrium with little or no effective atrial contraction. This condition may be chronic or intermittent, and it presently affects approximately 2 million or more people in the United States alone. For atrial fibrillation refractory to conventional drug therapy, it has been conventional practice to make incisions in the atrial wall, to surgically segregate the tissue thereof, to discontinue the atrial fibrillation. The atrial segments formed by the surgical segregation are electrically isolated and too small to allow the fibrillation to continue. However, the surgical technique is quite traumatic and is unacceptable to a large fraction of those patient's experiencing atrial fibrillation or flutter. Avitall in U.S. Pat. No. 5,487,385 discloses the use of high frequency electrical energy with a specific intravascular electrophysiological (EP) device to form linear ablations within a patient's atrial chamber to provide results similar to the surgical techniques in terminating atrial fibrillation but with significantly reduced trauma. However, the Avitall device cannot be readily placed within the patient's atrial chamber and provide the necessary contact between the electrodes on the device and the atrial tissue to generate linear lesions of a requisite length when RF electrical energy is emitted from the electrodes.
What has been needed is an ablation assembly which can be readily manipulated within a patient's atrial chamber to generate effective linear lesions at any desired location within the atrial chamber. The present invention satisfies these and other needs.